Conventional 2D matrix array probes coupled with current generation ultrasound systems are not fast enough to acquire clinically suitable volume sizes with the required temporal and spatial resolution for applications such as fetal heart imaging. According to current practice, a method was developed that divides the desired region-of-interest (ROI) into two or more partial volumes. Data is collected over each of these partial volumes over multiple heart cycles and then an entire 4D volume sequence is reconstructed by spatially and temporally stitching together volumes acquired from each of the partial volumes. The resulting 4D ultrasound data includes data from multiple cardiac phases for all of the partial volumes.
Relative motion between the anatomy in the ROI and the probe may result in motion artifacts that significantly reduce the quality of the 4D ultrasound data. In order to acquire and generate a high-quality image, it is important that the position of the ultrasound probe does not move with respect to the anatomical structure, such as a heart, being imaged. If relative movement occurs during acquisition, the resulting 4D ultrasound data may contain spatial artifacts and/or temporal artifacts visible as a discontinuity when viewing images generated from the 4D ultrasound data.
Since motion during the acquisition may result in image artifacts, it is important to acquire 4D ultrasound with as little unwanted motion as possible. When acquiring 4D ultrasound data of a heart as a group of partial volumes, it is necessary to perform the acquisition over multiple cardiac cycles. If any unwanted motion occurs, it will typically be detectable only when viewing a cine image, or a sequence of images over time, after the acquisition has been completed. If the artifact is severe enough, it may render the 4D ultrasound data unusable. If this is the case, it may be necessary for an operator to reacquire the 4D ultrasound data one or more times. According to conventional systems, the operator may be forced to iteratively complete a number of acquisitions before acceptable 4D ultrasound data has been successfully acquired. Repeated acquisitions waste time and are an inconvenience for both the operator and the patient.
For these and other reasons an improved method and ultrasound imaging system for acquiring 4D ultrasound data are desired.